Supersensitization of complex cyanine dyes



United States SUPERSENSITIZATION OF COMPLEX CYANINE DYES Jean E. Jones,Rochester, N.Y., assignor to Eastman Kodak Company, Rochester, N.Y., acorporation of New Jersey Filed July 29, 1957, Ser. No. 674,689

16 Claims. (Cl. 96-104) This invention relates to photographic emulsionscontaining complex cyanine dyes, and in supersensitizing combinationtherewith, certain sulfonated compounds.

It is known in the art of making photographic emulsions that certaindyes of the cyanine class alter the sensitivity of photographicemulsions of the gelatinosilver-halide kind, when the dyes areincorporated in the emulsion. It is also known that the sensitizationproduced by a given dye varies somewhat with the type of emulsion inwhich the dye is incorporated. Furthermore, the sensitization of a givenemulsion by a given dye may be altered by varying the conditions in theemulsion. For example, the sensitization may be increased by increasingthe silver ion concentration or decreasing the hydrogen ionconcentration (i.e., increasing the alkalinity) or both. Thus,sensitization can be increased by bathing plates, coated with aspectrally sensitized emulsion, in `water or in aqueous solutions ofammonia. Such a process of altering the sensitivity of a sensitizedemulsion by increasing the silver ion concentration and/or by decreasingthe hydrogen ion concentration is commonly called hypersensitization.Hypersensitized emulsions have generally poor keeping qualities.

I have now found another means of altering the sensitivity inphotographic emulsions containing complex cyanine dyes. Since theconditions in the emulsions, i.e., the hydrogen ion and/ or a silver ionconcentration, undergo little or no change in my method, I shalldesignate my method as a kind of supersensitization.

It is, therefore, an object of my invention to provide photographicemulsions containing complex cyanine dyes and, in supersensitizingcombination therewith, certain sulfonated compounds. Another object isto provide methods for making these emulsions. Other objects will becomeapparent from a consideration of the following description and examples.

By complex cyanine dyes, I mean a polymethine dye containing 2cyclammonium nuclei which have basic characteristics and oneheterocyclic nucleus derived from a ketomethylene compound having acidiccharacteristics.

Typical complex cyarn'ne dyes useful in practicing my invention comprisethose dyes represented by the following general formula:

ige

acid radical, such as chloride, iodide, bromide, perchlorate,p-toluenesulfonate, benzenesulfonate, ethylsulfate, methysulfate, etc.,Q represents a nitrogen atom or a methine group (=CH), D and D1 togetherrepresent the non-metallic atoms necessary to complete the4-thiazolidinone nucleus, S-thiazolidinone nucleus, or a4-imidazolidinone nucleus, and Z and Z1 each represents the non-metallicatoms necessary to complete a heterocyclic nucleus containing from 5 to6 atoms in the heterocyclic ring, such as those selected from the groupconsisting of those of the thiazole series (e.g., thiazole,4-methylthiazole, 4-phenylthiazole, S-methylthiazole, 5- phenylthiazole,4,5-dimethylthiazole, 4,5-diphenylthiazole, 4(2thienyl)thiazole, etc.),those of the benzothiazole series (e.g., benzothiazole,4-chlorobenzothiazo1e, S-chlorobenzothiazole, -chlorobenzothiazole,7-chlorobenzothiazole, 4-methylbenzothiazole, S-methylbenzothiazole, `6-methylbenzotbiazole, S-bromobenzothiazole, -bromobenzothiazole,4-phenylbenzothiazole, 5phenylbenzothiazole,

thoxybenzothiazolc, 5-iodobenzothiazole, 6-iodobenz0thazole,`l-ethoxybenzothiazole, S-ethoxybenzothiazole, tetrahydrobenzothiazole,5,-dirnethoxybenzothiazole, 5,6- dioxymethylenebenzothiazole,5-hydroxybenzothiazole, 6- hydroxybenzothiazole, etc.), those of thenaphthothiazole series (e.g., naphtho[l,2]thiazole,napht'ho[2,llthiazole, 5 methoxynaphtho[2,llthiazole, 5ethoxynaphtho[2,1] thiazole, 8-rnethoxynaphtho[1,2lthiazole,7-methoxynaphtho 1,2] thiazole, 6,7,8,9-tetrahydronaphtho [2, llthiazole, etc.), those of the thianaphtheno-7',6,4,5thiazole series(e.g., 4'-methoxythianaphtheno-'T,6,4,5thiazole, etc.), those of theoxazole series (e.g., 4-methyloxazole,5 methyloxazole, 4-phenyloxazole,4,5-diphenyloxazole, 4- ethyloxazole, 4,5-dimethyloxazole,5-phenyloxazole, etc), those of the benzoxazole series (e.g.,benzoxazole, 5chlo robenzoxazole, S-methylbenzoxazole, 5-phenylbenzoxazole, 6-methy1benzoxazole, 5,6-dimcthylbenzoxazole, 4,6-dimethylbenzoxazole, S-methoxybenzoxazole, 5-ethoxybenzoxazole,5-chlorobenzoxazo1e, 6methoxybenzoxazole, S-hydroxybenzoxazole,-hydroxybenzoxazole, etc.), those of the naphthoxazole series (e.g.,naphthollloxazole, naphtho-[2,l]oxazole, etc.), those of the selenazoleseries (e.g., 4methyselenazole, 4-phenylselenazole, etc.), those of thebenzoselenazole series (e.g., benzoselena'zole, 5-chlorobenzoselenazole, S-methoxybenzoselenazole,S-hydroxybenzoselenazole, tetrahydrobenzoselenazole, etc.), those of thenaphthoselenazole series (e.g., naphtho[1,2l selenazole,naphthollllselenazole, etc.), those of the thiazoline series (e.g.,thiazoline, 4-methylthiazoline, etc.), those of the Z-quinoline series(e.g., quinoline, 3-methylquinoline, S-methylquinoline,7-methylquinoline, 8- methylquinoline, I6-chloroquinoline,8-chloroquinoline, 6- methoxyquinoline, `6ethoxyquinoline,6-hydroxyquinoline, S-hydroxyquinoline, etc.), those of the 4quinolineseries (e.g., quinoline, -methoxyquinoline, 7-methylquinoline,

wherein R and R1 each represents an alcohol radical, i.e.,

an alkyl group (substituted or unsubstituted), such as methyl, ethyl,n-butyl, -hydroxyethyl, carboxymethyl, carbozyethyl, carbomethoxymethyl,carbethoxymethyl, -methoxyethyl, allyl (Le. vinylrnethyl), benzyl (i.e.phenylmethyl), etc., (especially alkyl groups containing from 1 to 4carbon atoms), R2 represents a hydrogen atom, an alkyl group (e.g.,methyl, ethyl, etc.), or an aryl group (e.g., phenyl, tolyl, etc.), n, mand d each repre- Sents a positive integer of from 1 to 2, X representsan 8-methylquinoline, etc.), those of the benzimidazole series (e.g.,1,3-diethy1benzimidazole, 1,3-diethyl-5-chlorobenzimidazole,l,3-diethyl-S,6-dichlorobenzimidazole, lethyl-3-phenylbenzimidazole,etc.), those of the 3,3-dialkylindolenine series (e.g.,3,3-dimethylindolenine, 3,3,5- trimethylindolenine,3,3,7-n`imethylindolenine, etc.) those of the 2pyridine series (e.g.,pyridine, S-methylpyridine, etc.), those of the 1f-pyridine series(e.g., pyridine, etc.),

etc.` t

Especially useful complex cyanine dyes selected from those representedby Formula I above include the dyes represented by the following twogeneral formulas:

and

group, such as those listed above with respect to R, and I represents asulfur atom or a ir-Rf' group wherein R represents an alkyl group, suchas methyl, ethyl, etc. (e.g., a lower alkyl group) or an aryl group(e.g., phenyl, tolyl, ete).

The sulfonated derivatives useful in practicing my invention comprisepolycarbocyclic aromatic compounds v vcontaining at least one sulfogroup. The term polynuclear aromatic as used herein is intended to mean2 or more benzene rings fused together (for example, as in naphthalene,pyrene, etc.) or at least 2 benzene rings or` aromatic rings directlyjoined together (for example, as in diphenyl, tei-phenyl, quaterphenyl,etc.) `or -through an aliphatic linkage. Such sulfonated derivatives canconveniently be represented by the following general formula:

(II) Ra.-S03M lwherein R3 represents a polynuclear aromatic group asdefined above and M represents a hydrogen atom or a Water-soluble cationsalt group (eg. sodium, potassium, ammonium, triethyl ammonium,triethanol ammonium, pyridinium, etc.). Among the most useful of thesulfonated derivatives embraced by Formula II above are the compoundsrepresented by the following general formula:

fcompounds selected from those represented by the follow- .ing generalformula:

(IIIa) 12.-( N-Nn Y NH- /N\ R, l N N t Y soa/r 08M Y R1 R5 wherein M hasthe values given above and R4, R5, R6, R7 each represents a hydrogenatom or a substituent group, suchY as hydroxyl, aryloxyl (e.g.,phenoxyl, o-

-toloxy1,.p-sulfopbenoxyl, etc.), alkoxyl (e.g., methoxy, 'ethoxyLetc.), a halogen atom (e.g., Chlorine, bromine, retc.), -a heterocyclicradical (e.g., morpholinyl, piperidyl, etc., an alkylthiogroup (eg.methylthio, ethyltbio, etc.),

anfarylthio group (e.g., phenylthio, tolylthio, etc.), aheterocyclylthiogroup (e.g. benzothiazylthio, etc.), an amino group, analkylamino group (e.g., methylamino,

ethylamino, propylamino, dimethylamino, diethylamino,

-dodecylamino, cyclohexylamino, -hydroxyethylamino,

di--hydroxyethylamino, -sulfoethylamino, etc.), an arylamno group (e.g.,anilino, o, m, and p-sulfoanilino, o, m, and p-chloroanilino, o, m, andp-anisylamino, o, m, and p-toludino, o, m, and p-carboxyanilino,hydroxyanilino, sulfonaphthylamino, o, m, and p-aminoanilino,p-acetamidoanilino, etc.), etc.

Compounds of Formula IIIa wherein R4, R5, R6 and/ or R7 each representsa heterocyclylamino group (e.g., 2- benzothiazoleamino, 2pyridylamino,etc.) can also be used in practicing my invention.

Another group of sulfonated derivatives which are useful in practicingmy invention are those represente bythe following general formula:

(Iv) o V0 R Re wherein R8 is an acylamido group (e.g., acetamido,sulfobenzamido, 4methoxy-3sulfobenzamido, 2-ethoxybenzamido,2,4-diethoxy, benzamido, p-tolylarnido, 4- methyl-Z-methoxybenzamido,l-naphthylamido, Z-naphthylamido, 2,4-dimethoxybenzamido,2phenylbenzamido, 2-thienylbenzamido) or a sulfo group, R9 represents anacylamido group (e.g., as defined by R8 above), or a sulfoaryl group(e.g., sulfophenyl, psulfodiphenyl, etc.) and Rm represents a hydrogenatom or a sulfo group, said compound containing at least `one sulfogroup.

The complex cyanine dyes selected from those represented by Formulas I,Ia and Ib above, have, in general, been previously described in theprior art. Among the references describing the preparation of such dyesare the following:

` Inventor Patent No Issue Date Douglas I ames Fry and John David 2,388,963 Nov. 13, 1945.

Kendall. .lohn David Kendall 2,430,295 Nov. 14, 1947. Oskar Riester andGustav Wilmanns 2,440,119 April 20, 1948. Oskar Riester 2,442, 710 .Tune1, 1948. Leslie G. S. Brooker... 2, 454, 629 Nov. 23, 1948. Thomas R.rlhompson 2, 504, 468 April 18, 1950. Henry G. Derbyshire. 2,535,982Dec. 26, 1950. Thomas R. Thompson 2, 535, 993 Dee. 26, 1950. Per Aubert,Roy A. Jelreys and 2, 656, 351 f Oct. 20, 1953.

Edward B. Knott.

Several `of the examples below describethe preparation of typicalcomplex cyanine dyes useful in practicing my invention.

Compounds of Formula IIIa which can advantageously be employed inpracticing my invention have been described in one or more of thefollowing representative patents:

U.S. 2,171,427, August 29, 1939; 2,473,475; .lune 14, 1949; 2,595,030,April 29, 1952; 2,660,578, November 24, 1953.

British 595,065, November 26, 1947; 623,849, May 24, 1949; 624,051, May26, 1949; 624,052, May 26, 1949; 678,291, September 3, 17952; 681,642,October 29, 1952; 705,406, March 10, 1954.

The products of Formula IIIa have been previously employed lin thetextile ield, and are sold under such tradenames as Leucophor B,Calcofluor White MR, Tinopal (SP, WR, BV277, 2B, GS, NG), Blancofor SC,

Hiltamine (BSP, N, Sol., 6T6), and the like. Y

The preparation of a number of compounds employed by Formula Illa abovehas been previously described in the copending application Serial No.540,052 ofV B. H. JCarroll, I. E. Jones and I. Spence, led October l2,1955.

'Ihe dibenzothiopbenedioxide compounds of Formula IV have, in general,been previously described inthe prior art. See, for example,V U.S.Patents 2,573,652; 2,580,234; and 2,563,493. Further examples of thepreperation of such lmtripoundsY are given'in thejcopending applicationof I; E. Iones,`I. 'Spence and I. A. Van Allan, Serial No. 575,160, ledMarch 30, 1956. Other examples of sulfonated derivatives embraced byFormula YII above which an advantageously be used in my invention can beprepared according to the methods described in application Serial No.575,160. Other examples of compounds represented by Formula II abovewhich can be used in my invention have been previously described in thecopending application of B. H. Carroll, I. E. .Tones and I. Spence,Serial No. 540,054, tiled October 12, 1955. (See, in particular, thecompounds of Formulas II, III and IV of that application.)

Compounds selected from those of Formula III above wherein B1 representsa 2-benzotriazolyl group can be prepared according to methods previouslydescribed in the prior art. See, for example, U.S. Patent 2,713,067,dated July l2, 1955. A somewhat related group of compounds containing aZ-benzotriazolyl group which can be used in my invention have beenpreviously described in U.S. Patent 2,733,165. Such compounds areembraced by Formula II above.

Typical sulfonated derivatives embraced by Formulas II, III, IIIa and IVabove are:

(1) A sulfonated triazolostilbene, e.g., of the type shown in U.S.Patent 2,713,057.

(3) 4,4 -bis[3 3' sulfoanilino) 5 amino s triazinyl amino stilb ene.

(4) Tinopal-WR, a sulfonated triazinyl stilbene.

(5) Tinopal-ZB, a sulfonated triazinyl stilbene.

(6) A sulfonated triazinyl stilbene, e.g., of the type shown in U.S.Patent 2,595,030 or British 595,065. (7) 4,4 bis[2 (4 sulfoanilino 4hydroxyethylamino) 1,3,5 triazin 6 ylamino]stilbene 2,2 disulfonic acid.

(8) 4,4 bis(2,4 dihydroxy 1,3,5 triazin 6 ylamino)dibenzyl-2,2disulfonicacid.

(9) 4,4 bis(2 hydroxyethylamino 4 anilino- 1,3,5 triazin 6 ylamino) 1,4distyrylbenzene- 2,2disulfonic acid.

(l0) 5 methoxy 2 (4 stilbyl) 1,2,3 benzotriazole-2sulfonic acid.

(1l) Calcofluor White-MR, a sulfonated triazinyl stilbene.

(12) p-Quaterphenyl4,4disulfonic acid.

(13) 3,7 bis(2 phenylbenzamido) 2,8 disulfodibenzothiophene5,5dioxide.

(14) 3,7 bis(2 thienylarnido) 2,8 disulfodibenzothiophene dioxide sodiumsalt.

(15) 3 [4 (4 methoxy 3 sulfobenzamido)phenyl] 7-(4 methoxy 3sulfobenzamido)dibenzothiophene dioxide sodium salt.

(16) Chrysene--sulfonic acid sodium salt.

( 17) Pyrene-3-sulfonic acid sodium salt.

(18) Phenanthrene-3-sulfonic acid sodium salt.

(19) 2,3 dimethylnaphthalene 1 sulfonic acid sodium salt. l.

(20) 4 [4 phenoxy 6 hydroxyethylamino) striazin 2 ylamino] 4 [4 chloro 6di( hydroxyethyDamino s triazin 2 ylamino]stilbene 2,2-disulfonic acid.

(21) 2,8 bis[4 (4 sulfoanilino) 6 hydroxy s-triazin-2-ylamino]carbazole.

(22) 2 (3 sulfoanilino) 6 hydroxy 4 hydroxyethyl) amino-s-triazine.

(23) 4,4' bis(4,6 di( hydroxyethylamino) striazin-2-yl)benZidine2,2-disulfonic acid.

(24) 2-laurylamino-4,6-di(4-sulfoanilino) -s-triazine.

AS can be seen above, many of the sulfonated derivatives are employed inthe form of their water-soluble salts, such as alkali metal (e.g.,sodium, potassium, etc.) salts, or ammonium or amine (e.g.,triethylamine, triethanolamine, pyridine, aniline, etc.) salts. By thususing these derivatives, they can be added to the emulsions insubstantially neutral aqueous solutions without disturbing the pH of theemulsions.

According to my invention, I incorporate one or more of the complexcyanine dyes selected from those represented by Formula I (or Ia or Ib)above with'one or more of the sulfonated derivatives of the typedescribed above in a photographic emulsion. My invention is particularlydirected to the ordinarily employed gelatinesilver-halide emulsions.However, my supersensitizing combinations can be employed in silverhalide emulsions in which the carrier is other than gelatin, e.g., aresinous substance or cellulose material which has no deterioratn effecton the silver halides.

The complex cyanine dyes and sulfonated derivatives can be employed invarious concentrations depending upon the effects desired. As is Wellknown in the art, the sensitivity conferred upon an emulsion by asensitizing dye does not increase proportionately to the concentrationof the dye in the emulsion, but rather passes through a maximum as theconcentration is increased. In practicing my invention, the complexcyanine dyes are advantageously employed in a concentrationapproximating their optimum concentration (i.e., the concentration atwhich the dye gives greatest sensitivity). In general, the sulfonatedderivatives employed in my invention have little or no sensitizingaction in the emulsions employed.

The optimum concentration of an individual sensitizing dye can bedetermined in a manner Well known to those skilled in the art bymeasuring the sensitivity of a series of test portions of the sameemulsion, each portion containing a different portion of the sensitizingdye. The optimum concentration of the complex-cyanine dyes used in myinvention can, of course, be readily determined in the same manner bymeasuring the sensitivityof a series of test portions of the emulsion,each portion containing a different concentration of the complex cyaninedye to be used in the combination. In determining the optimumconcentration for the supersensitizing combination, it is advantageousto employ at first a concentration of the complex cyanine dye less thanits optimum concentration, and then gradually increase the concentrationof thedye until its optimum concentration is determined.

Ordinarily, the optimum or near optimum concentration of the complexcyanine dyes useful in practicing my invention is of the order of from0.02 to 0.3 g. per mole of silver halide in the emulsion.

The sulfonated derivatives useful in practicing my invention canadvantageously be employed in concentrations on the order of from 0.02to 10.0 g. per mole of silver halide in the emulsion.

Generally speaking, the ratio of concentration of the complex cyaninedye to the sulfonated derivative can vary rather widely in mycombinations, eg., from 1:100 to 1:1 (by Weight) in many instances.

The methods of incorporating sensitizin g dyes in emulsions are wellknown to those skilled in the art, and as mentioned above, thesulfonated derivatives of my invention can be incorporated in theemulsions conveniently in substantially neutral aqueous solution. Inpracticing my invention, the complex cyanine dyes and sulfonatedderivatives can be incorporated in the emulsions separately or together.Frequently, it is convenient to add the complex cyanine dyes andsulfonated derivatives separately in the form of solutions inappropriate solvents. Methanol, ethanol, pyridine, etc., have provensatisfactory as solvents for the complex cyanine dyes which I employ inmy invention, although acetone has also been found to be satisfactory incertain cases. If desired, a mixture of solvents, such as methanol andpyridine, can

'7 'be employed. The complex cyanine dyes and sulfonated derivatives canbe added to the emulsions in any given order. The complex cyanine dyesand sulfonated derivatives are advantageously incorporated in thenished, washed emulsions and should be uniformly distributed throughoutthe emulsions. The following procedure 1s satisfactory: Stock solutionsof the dyes and sulfonated derivatives desired are prepared bydissolving the same in appropriate solvents as described above. Then, tothe owable gelatino-silver-halide emulsion, the desired amounts of thestock solution of one of the dyes (or sulfonated derivatives) is slowlyadded, while stirring the emulsion. Stirring is continued until the dyeis thoroughly incorporated in the emulsion. Then, the desired amount ofthe stock solution of the sulfonated derivative (or dye, if sulfonatedderivative has been added first) is slowly added to the emulsion, whilestirring. Stirring is continued until the second ingredient isthoroughly incorporated. The supersensitized emulsion can then be coatedout on a suitable support, such as glass, cellulose derivative iilrn,resin lm, or paper, to a suitable thickness andallowed to dry. Thedetails of such coating methods are well known to those skilled in theart.

The amounts of the complex cyanine dyes and sulfonated derivativesactually incorporated in the emulsion will vary somewhat from case tocase, according to the emulsion employed and according to the effectdesired. The regulation and adoption of the most economical and usefulproportions will be apparent to those skilled in the art upon making theordinary observations and tests customarily employed in the art.Accordingly, the foregoing procedures and proportions are to be regardedonly as illustrative. Clearly, my invention is directed to any emulsioncontaining a combination of the aforesaid complex cyanine dyes andsulfonated derivatives whereby a supersensitizing effect is obtained.

My invention is primarily directed to the ordinarily employedgelatino-silver-halide developing-out emulsions, e.g.,gelatino-silver-chloride, -chlorobromide, -chloroiodide,-chlorobromiodide, -bromide and -bromiodide developing-out emulsions.While the results in the following table were obtained usinggelatino-silver-bromiodide emulsions, excellent results have also beenobtained using gelatino-silver-chlorobromide emulsions. Emulsions Awhichform the latent image mostly inside the silver halide grains, such asthe emulsions set forth in U.S. Patent 2,456,956, dated December 2l,1948, canalso be employed in practicing my invention.

Photographic silver halide emulsions, such as those listed above,containing the supersensitizing combinations of my invention can alsocontain such addenda as chemical sensitizers, e.g., sulfur sensitizers(e.g., allyl thiocarbamide, thiourea, allylisothiocyanate, cystine,etc.), various gold compounds (eg. potassium chloroaurate, aurictrichloride, etc.) (see U.S. Patents 2,540,085; 2,597,856'and2,597,915), various palladium compounds, such as palladium chloride(U.S. 2,540,086), potassium chloropalladate (U.S. Patent 2,598,079),etc., or mixtures of such sensitizers; antifoggants, such as ammoniumchloroplatinate (U.S. 2,566,245), ammonium chloroplatinite (U.S.2,566,263), benzotriazole, nitrobenzimidazole, S-nitroindazole,benzidine, mercaptans, etc. (see Mees-The Theory of the PhotographicProcess, Macmillan Pub., 1942, page 460), or mixtures thereof;hardeners, such as formaldehyde (U.S. 1,763,533), chrome alum (U.S.1,763,533), glyoxal (U.S. 1,870,354), dibromacrolein (Br. 406,750),etc.; color couplers, such as those described in U.S. Patent 2,423,730,Spence and Carroll U.S. Patent 2,640,776, issued June 2, 1953, etc.; ormixtures of lsuch addenda. Dispersing agents for color couplers, such asthose set forth in U.S. Patents 2,322,027 and 2,304,940, can also beemployed in the above-described emulsions.

The following examples will serve to illustrate further the manner of'practicing my invention. To different portions of the same batch ofphotographic gelatino-silverbromiodide emulsion vwere added (1) acomplex cyamne dye of Formulas I, la or Ib and (2) a combination of thecomplex cyanine dye and a sulfonated derivative as described above.Before coating, the emulsions containing the addenda were digested for ashort time in a tank maintained at 50-52 C. The different portions ofemulsion were then coated on conventional supports and exposed in theusual manner in a spectrograph and Eastman Type Ib Sensitometer througha Wratten 25 Filter, i.e., a ilter which transmits substantially nolightof wavelengths shorter than about 580 ma, except in Examples 25 and41 where a Wratten No. 58 Filter, i.e., a -lter which transmits onlylight of wavelengths lying between 465 and 620 ma, and Examples 47 and48 where a Wratten No. 12 Filter, i.e., a filter which transmitssubstantially no light of wavelengths shorter than 495 my., were used.The exposed coatings were then processed for about 3 minutes in adeveloper having the following composition:`

G. N-methyl-p-aminophenolsulfate 2.0 Hydroquinone 8.0 Sodium sulte(anhydrous) 90.0 Sodium carbonate (monohydrate) 52.5 Potassium bromide5.0

Water to make one liter.

As mentioned above, no data showing the sensitometric properties of thesulfonated derivatives alone are given, since it has been found that thederivatives have little or no sensitizing action on the emulsions used.Different emulsions were used in some of the examples, although theemulsions of each individual example were obtained from the same batch.In Table A, all `of the coatings were obtained from the same batch ofemulsion, while in Table B, thecoatings of Examples 13-16 Werevobtainedfrom the same batch of emulsion; the coatings of EX- amples 17-21 wereobtained from the same batch of emulsion; the coatings of Examples 22-24were obtained from the same batch of emulsion; the coatings of Examples25-27 were obtained from the same batch of emulsion; the coatings ofExamples 28-31 were obtained from the same batch of emulsion; thecoatings of Examples 32-36 were obtained from the same batch ofemulsions; the coatings of Examples 37-44 were obtained from the samebatch of emulsions; the coatings of Examples 45-49 were obtained fromthe same batch of emulsions, the coatings of Examples 50 and 51 wereobtained from the same batch of emulsion and the coatings of Examples52-56 were obtained from the same batch of emulsion. The purpose of thedata in Table A is to show that the useful results of my invention areobtained with different sulfonated derivatives when asingle complexcyanine dye is used for comparison, while Table B shows that similareffects are obtained even where the complex cyanine dye is varied instructure.` The speed (red, except for Examples 25, 41, 47 and 48),gamma and fog for each of the coatings are given in Tables A and B. Thespeed gure used is represented by the formula (1-log E) where Erepresents the exposure in meter candles seconds required to provide adensity of 0.3,. It is to be noted that small diierences in speed arequite signicant, since a difference of 30 units represents a speeddierence of 100% (i.e., log 1 .30 is 2).

It is to be noted from the above tables that dyes of Formulas I, Ia, orIb above can be used in my invention, where R or R1 represents analkylene group (dimethylene or trimethylene) which is attached to theperi-position of ay benzene ring which forms a part of the Z or Z1heterocyclic nucleus. This alkylene group then denes a hydrogenatedpyrrole or pyridine ring, which is fused tothe heterocyclic4 ringdefined byZ and Z1. An example of the preparation of such a dye is givenbelow.

Senstizlng Dam Example .Addenda (g.lmo1. AgX) Speed Gamme Fog 35 (11")dye (b") (.08) plus compound 13 (.08) 100 2.6 .05 2-[(2benzothlazo1y1ethiodide)methylene]-3cthy15-[(3ethy1 93 2.8 .06 36 2((351)-benzoxazo1y1idene)ethy1idene] 1 phenyl 4 imdazolidinone (f') dye(6) (.08) plus compound 13 (.08) 104 2.9 .06 2[(2benzothlazolylethicd1de)methylene]5-[(3ethyl2(3H)-lsenz-V 71 3.0 .07

othiazolylidene)ethylidene]-3-methy1-4-thiazolidinone (.08). (11) dye(0) (.08) plus compound 10 (.08) 88 2.8 .05 dye (41) (.08) plus com onnd13 (.08) 103 2.6 .05 (j) 3ethy1-5-[(lethy12(1)'-naphthothizaolylidene)ethylde 110 2.9 .06 [(2-B-napl1thothlazoly1ethiodlde)methylene]-4-thiazolidinone (.08). (k) dye (1") (.08).pluscompound 10 (.08) 124 2.7 .06 (1) 2-[(2benzoth1azo1ylethoperchlorate)methylene 5 [(3-ethyl-2- 100 3.0 .O4 o(301-81)benzoxazolylidene)ethylldene]-1,B-diphenyl-l-imdazolidnone (m)dye (1") (.08) plus compound 13 (.08) 111V 2.9 .06 (11)2[(2benzothlazolyl ethiodlde)methy1ene]-3ethyl5(3ethyl2 98a 3.1 .05 41(3H)benzothiazolylidene)4-thiazo1idinone (.08).

0) dye (11) (.08) plus compound 13 (.08) 115e 3.0 .053-ethy1-5-[(3-ethy1-2(3H)benzothiazolylidene)ethylidene]2[(2 3.0 .06lllitholghiazolyl etho-p-toluenesulfonate)methy1ene]4thiazo one (4") dye(11) (.08) plus compound 10, (.08) 107 3. 3 .08 (r") dye (11") (.08)plus compound 13 8.08) 97 3.3 .06 2- (2-benzothlaz01y1benzobromidemethylene -ethyl5-[(3ethyl 91 2.5 .06

2-(3 -benzothiazolylidene)ethylidene]4thlazolidinone (.08). (t) dye (3)(.08) plus compound 13 (.08) 110 2. 5 .06 (2) 2-[(2-benzose1enazo1y1ethiodide)methylene]4[(3-ethyl-2(3H) 71 3.0 .07 45benzoxazolylldene)ethylldene]-3-methy1-5-thiazolidinone (.08).

(0) dye (11") (.08) plus compoundlo (.08) 97 3.3 .05 46 (w) dye (u")(.08 plus compound 13 (.08) 98 3.2 .07 [(z) 2[(2thlazoliny1methlodide)methy1ene]-4[(3ethyl (3H)benz 107b 3.4 .06 47 ioxazolylldene)ethylidene]-3-methy1-5-thiazolidnone (.08).

dye (z") (.08) plus compound 13 (.08) 121b 3.2 .06 (2" 2-[(2thlazo1iny1methlodide)methylene]-5[(3-ethyl-2(3H)benz Y 87h 3.2 .06 48oxazolylidene)ethylldene]-3-methyl-4thiazo1idinone (.08).

(am) dye (2) (.08) plus compound 13 (.0 1126 2.9 .07 (b)2-[(4,5-dlpheny1thlazolyl ethiodide)methylene]-3ethy1-5[(3 110 2.7 .0649 ethyl-2(3H)6,7,8,9tetrahydronaphtho[2,1]thlazo1yl1dene)-1-phenyl- Yethyldenel-i-thiazolidinone (.08). Y

(c) dye (b' (.08) plus compound 10 (.08) 121 2.7 .06 (d')2[(2benzothlazolyl ethiodide)imino]5-[(3Jethyl2(3H)benzothi- 20 2. 6 .06

azolylldene)ethylidene]-3-phenyl4thiazo1idinone (08) (e") dye (d") (.08)plus compound 10 (08)-..- 50 2. 6 .07 (f) dye (d) (.08) plus compound 13(.08).. 55 2.8 .06 ((gm) 3ethy12-[(2 enzoxazolyl ethiodide)meth 72 3.2.06

2(1H)quinolylidene)ethy1ldene]-4thlazolidinone (.08). (h) dye (g) (.08)plus compound 13 (.08) 94 3.1 .06 (im)3-ethy1-2-[(5-phenyl-4-p-xy1y1-2-thiazolyl methiodide)methy1 78 2.6 .0553 ene] -5 [(3-methy1-5-pheny1-4-p-xylyl-2 (3H) -thiazolylidene)ethyl1denel-4-thlazolidinone (.08)..

dye (l) (.08) plus compound 10 (.08) 89 3.0 .05 (k")2-[(2benzose1enazollny1 ethiodlde)methy1ene]4[(3ethyl2(3H) 57 2.6 .06 64benzoselenazolylidene)ethylldene]3methyl5thiazo1idinone (.08). Y

(11") dye (km) (.os) plus compound 13 (.08) Y8o 3.2 .05 (m)2[(2benzoselenazolinyl ethiodide)methylene]5 [(3-ethyl-2(3H) 69 3.3 .0455 benzoselenazolylldene)ethy1idene]3-ethyl-l-thiazol none (.08)

(nm) dye (m") (.08) plus compound 13 (.08) 88 Y 3.0 .05 (o)2-[(4-p-anisyl-5phenylf2thiazo1yl ethlodlde)methylene] 46 3.0 .06 56 iethyl-2(3H)benzoxazolylidene)ethylldene]-3-ethyl-4-thlazolid1none (pm)dye (o) (.08) plus compound 13 (.08) 60 3 5 .07

=green speed. b=minus blue speed.

2(1H) naphtho[1,2]thia'zo1ylidene) a phenylethylideneJrhodanine and 3.7g. of methyl p-.toluenesulfonate was heated at the temperature of thesteam bath for.4 55 n 6,7 ,8,9-tetrahydronaphtho[2,llthiazolylidene)1-phenylethylidenel-'rhodanine (PB Report 74175, page 00401.)

hours. The resulting product was washed with acetone,- and then it wascondensedw'ith 3.05V g. o-f 3-ethyl-2`f methylbenzothiazolium iodide in25 ml. of dry pyridine containing 1.0 g. of triethylamine by heating thereaction mixture at the reuxing temperature -for 15 minutes. 70

After chilling, the solids were collected on a filter and washed withmethyl alcohol. The yield of dye after two recrystallizations frommethyl alcohol was 7%. The

.dark green crystals melted at 22,4-226 C. with desemposition.

nA minore er ons er s ethyi-'s-methyl-MH)- and 0.37 g. of methylp-toluenesulfonate was fused over a free flame and then heated in an oilbath at -120 C. -for 9() minutes. The resulting crude product was'condensed with 0.80 g. of l-ethyl-Z-methylnaphthoE1,2]l j Vthazoliumptoluenesulfonate in l5 m1. of dry pyridine by heating the Vreactionmixture at therefluxng tempera- Sodium bromide in 25 m1. of water wasadded vto the 1101:

- washed irst with acetone and then water.

reaction mixture. After chilling, the dye was collected `on va filter-and Washed rst with ether and then with water. The yield of dye aftertwo recrystallizations from methyl alcohol was 77%. The brownish-greencrystals melted at 219-220" C. with decomposition.

A mixture of 4.1 g. of [(3benzyl2(3H)-benzo thiazolylidene) ethylidenel-3-ethylrhodanine and 3.7 g. of methyl p-toluenesulfonate was fused overa free flame and then heated at the temperature of the steam bath fortwo hours. The resulting product was washed with absolute ether, andthen it was condensed with 3.2 g. of2-methyl3,4-trimethylenebenzothiazolium `iodide in 25 ml. of drypyridine containing 1.0 g. of triethylamine by heating the reactionmixture at the reuxing temperature for minutes After chilling the dyewas collected on a lter and Washed with methyl alcohol. The yield ofdyevafter two recrystallizations from methyl alcohol was '16%. The darkgreen crystals melted at 288-290 C. with decomposition.

A mixture of 1.0 g. of 5-[(5chloro-1,3iiethyl2(3H)-benzimidazolylidene)ethylidenel3ethy1rhodanine and 3 ml. of methylp-toluenesulfonate was heated over a free llame for about 3 minutes. Theresulting product was washed with absolute diethyl ether, and then itwas condensed with 1.0 g. of 5-chloro-3-ethyl2methylbenzo thiazoliumiodide in ml. of absolute ethyl alcohol containing 3.,5 ml. oftriethylamine by heating the reaction Amixture at the reuxingtemperature for about one minute. After chilling, the dye was collectedon a filter and The yield of dye after two recrystallizations frommethyl alcohol was 30%. The `green crystals melted at 321-322 C. withdecomposition.

C ZH5 'thiocyanate and chloroacetic acid) and 2.17 g. of 2-,8-

acetanilidovinyl-3ethylbenzoxazolium iodide in 25 m1. of

"absolute ethyl alcohol containing 1.0 ml. of triethylamine was heatedat the refluxing temperature for minutes.

After chilling, the dye was collected on a lter and washed rst withwater, then acetone and nally methyl alcohol. The dye was dissolved inhot cresol, the solution was ltere'd and methyl alcohol was added to theltrate. After chilling, the dye was collected on a lter and washed withmethyl alcohol. After another such treatment, the yield of dye was 40%.'Ihe dull purplish needles with a green reflex melted at 26S-266 C. withdecomposition. (Cf. U.S. Patent 2,535,982.)

A mixture of 1.11 g. of 3-ethyl-5[(3etl1y1-2(3H)benzoxazolylidene)ethylidene)rhodanine and 1.0 g. of methylp-toluenesulfonate Was fused over a free ame and then. heated at thetemperature of the steam bath for two hours. The crude product wascondensed with 1.25 g. of V2-(2-ethoxypropenyl)-3-ethylbenzothiazoliumiodide `in 20 ml. of absolute ethyl alcohol containing 0.7 m1. of

triethylamine by heating the reaction mixture at the reuxing temperaturefor 30 minutes. After chilling, the dye Was collected on a lter andwashed with methyl alcohol. The yield of `dye after tworecrystallizations from methyl alcohol was 47% The dark green crystalsmelted at 207-208 C. with decomposition.

In exactly the manner shown above, other dyes useful in my invention canbe prepared. 'Ihe following table gives the melting points of a numberof dyes related to those of Examples A-F.

MELTING POINTS FOR RELATED DYES M.P., C. (with decomposition) Dye:

p 291-292 t 284-286 x 323-325 p 293-295 r 282-284 w' 282-284 y 284-285 b293-295 e" 291-293 g S10-312 j 247-249 l 181-184 n 274-276 p" i 256-258s" 246-248 z" 304-306 b" 262-263 d" 258-259 g" 298-300 i" 237-239 k280-281 The `accompanying drawing illustrates the supersensitizing eiectobtained with three of my new combinations "in gelatino-silverbromiodideemulsions.

containing the complex cyanine dye of Formula I above 10 is representedby the solid lower curve. The upper curve (dotted line) represents thesensitivity conferred on the emulsion by the combination of the complexcyanine dye of Formula I with one of the sulfonated compounds of myinvention. No `curve illustrating the effect of 4the 15 sulfonatedcompound alone is shown, inasmuch as it has been found that thesesulfonated compounds have little orno measurable eiect on thesensitivity of the emulsions.

In Figure 1, curve A represents the sensitivity of an 20 idinone, whilecurve B represents the sensitivity of the 25 metric measurements forthese emulsions are given in 'Example 10 of the above table.

In Figure 2, curve C represents the sensitivity of an ordinarygelatino-silver-bromiodide emulsion sensitized with2[(S-chloro-Z-benzothiazolyl etho-p-(toluenesulfo- 35 thiazolyl etho ptoluenesulfonate)methylene] 3- 40 ethyl 5 [(3 ethyl 2(3H)benzothiazolylidene) a-phenylethylidenel -4-thiazolidinone and3,7bis(2-phen ylbenzamido) ,2,8 disulfodibenzothiophene 5,5 dioxide. Thesensitometric measurements for these emulsions are given in Example 18of the above table.

lIn Figure 3, curve E represents the sensitivity of an ordinarygelatine-silver-bromiodide emulsion sensitized amine, triethanolamine,pyridine, picolines, etc.). As

mentioned above, one advantage of adding the sulfonated derivatives inthe form of their salt solutions is that the pH of the solution is notdisturbed. However, when using small quantities of sulfonatedderivatives, the free acids can also be used to advantage.

What I claim -as my invention and desire secured by .Letters Patent ofthe United States is:

1. A `photographic silver halide emulsion sensitized The sensito- 30with a supersensitizing combination of (a) at least one complex cyaninedye selected from the class represented by the following generalformula:

wherein R and R1 each represents an alkyl group, R2 represents a memberselected from the group consisting of a hydrogen atom, an alkyl group,and an aryl group, Q represents a member selected from the groupconsisting of a methine group and a nitrogen atom, X represents an acidradical, n, m and d each represents a positive integer of from 1 to 2, Dand D1 together represent the non-metallic atoms necessary to complete aheterocyclic nucleus selected from the group consisting of those of the4thiazolidinone series, those of the S-thiazolidinone series, and thoseof the 4-imidazolidinone series, and Z and Z1 each represents thenon-metallic atoms necessary to complete a heterocyclic nucleuscontaining from 5 to 6 atoms in the heterocyclic ring selected from thegrop `consisting of those of the thiazole series, those of thebenzothiazole series, lthose of the naphthothiazole series, those 'ofthe thianaphtheno7,6,4,S-thiazole series, those of the oxazole series,those of the benzoxazole series, those of the naphthoxazole series,those of the selenazole series, those of the benzoselenazole series,those of the naphthoselenazole series, those of the thiazoline series,those of the 2-quinoline series, those of the 4-quinoline series, thoseof the benzimidazole series, those of the 3,3-dialkylindolenine series,those of the 2-pyridine series, and those of the 4-pyridine series, and(b) at least one water-soluble compound selected from the classrepresented by the following general formula:

Awherein R3 represents a polynuclear aromatic group and wherein Rand R1each represents an alkyl group, R2 represents a member selected from thegroup consisting of a hydrogen atom, an alkyl group, and an aryl group,Q represents a member 4selected `from the group consisting of a methinegroup and ya nitrogen atom, X represents an acid radical, n, m and deach represents a positive integer of from 1 to 2, D and D1 togetherrepresent the nonmetallic atoms necessary to complete a heterocyclicnucleus selected from the group consisting of those of the4-thiazolidinone series, those of the S-thiazolidinone series, and thoseof the 4-imidazolidinone series, and Z and Z1 each represents thenon-metallic atoms necessary to complete -a heterocyclic nucleuscontainingA from 5' to 6 atoms in the heterocyclic ring selected fromthe group consisting of those of the thiazole series, those of thebenzothiazole series, those of the naphthothiazole series, those ofthethianaphtheno-7,6',4,S-thiazole series, those of the oxazole series,those of the benzoxazole series, those of the naphthoxazole series,those of the selenazole series, those of the benzoselenazole series,those of the naphthoselenazole series, Vthose of the thiazoline Series,

those of the 2-quinoline series, those of the 4-quinoline series, thoseof .the benzimidazole series, thoseV of the .3,3-dialkylindolenineseries, those of the Z-pyridine series, those of the `.lpyridine series,and (b) at least one 1 1 i Water-soluble compound selected from theclass 'represented by the following general formula:

onion-Bg SOaM wherein B1 represents ra member selected from the groupconsisting of a 2-benzotriazolyl group and a 1,3,5atriazin- 6-,ylaminogroup, B2 represents an aromatic group, an M represents a cation.

3. A photographic silver halide emulsion sensitized with asupersensitizing combination of (a) `at least one complex cyanine dyeselected from the class represented by the 'following general formula:

ofivgeeo r 18 I represents a member selected from the group consistingof a sulfur atom and a Nl'uRI group wherein R" represents a memberselected from the group consisting of an alkyl group and an aryl group,X represents an acid radical, d represents. a positive integer of from lto 2, and Z and `Z1 each represents the non-metallic atoms necessary tocomplete a heterocyclic nucleus selected from the group consisting ofthose of the thiazole series, those of the benzothiazole series, thoseof the naphthothiazole series, those the thiazoline series, those of thebenzoxazole series, those of the benzoselenazole series, those of thebenzimidazole series, and those of the 2-quinoline series, and (b) atleast one wherein R and R1 each represents an alkyl group, R2 21jwater-soluble compound selected from the class reprerepresents a memberselected from the group consisting of a hydrogen atom, an alkyl group,and an aryl group, Q represents a member selected from the groupconsisting of a methine group and a nitrogen atom, X represents an acidradical, n, m and d each represents a positive integer of from l to 2, Dand D1 together represent the nonmetallic atoms necessary to complete aheterocyclic nucleus selected lfrom the group consisting of those of the4-thiazolidinone series, those of the S-tliiazolidinone series, andthose `of the 4-imidazolidinone series, and Z and Z1 each represents thenon-metallic atoms necessary to complete a heterocyclic nucleuscontaining from 5 to 6 atoms in the heterocyclic ring selected from thegroup consisting of those of the thiazole series, those of thebenzothiazole series, those of the naphthothiazole series, those of thethianaphtheno-7,6,4,5thiazole series, those of the oxazole series, thoseof the benzoxazole series,

those of the naphthoxazole series, those of the selenazole` series,those of `the benzoselenazole series, those of the naphthoselenazoleseries, those of the thiazoline series, those of the 2-quinoline series,those of t the 4-quinoline series,- those of the benzimidazole series,those of the 3,3-dialkylindolenine series, those of the Z-pyridneseries, and those vof the 4pyr-idine series, and (b) at least onewater-soluble compound selected -from the class represented by thefollowing general formula:

wherein R, R1 and R each represents an alkyl group, R2

representsa member selected from the group consisting' of'a hydrogenatom, an alkyl group and an iary-l group,

sented by the following general formula:

SOsM

wherein B1 represents a member selected from the group consisting of a2-benzotriazolyl group and a 1,3,5-triazin- 6-ylamino group, B2represents an aromatic group, and M represents a cation.

5. A photographic silver halide developing-out emulsion sensitized witha supersensitizing combination of (a) at least one complex cyanine dyeselected from the class represented by the following generalformula:

wherein R, R1 `and R each represents an alkyl group, R2 represents amember selected from the group consisting of a hydrogen atom, an `alkylgroup and an aryl group, J represents a member selected from the groupconsisting of a sulfur atom and a t f if-R" group wherein Rrepresents amember selected from the group consisting of an alkyl group and an .arylgroup, X represents an acid radical, d represents a positive integer of'from 1 to 2, and Z and Z1 each represents the nonmetallic atomsnecessary to complete a heterocyclic nucleus selected from the groupconsisting of those of the thiazole series, those of the benzothiazoleseries, those of the naphthothiazole series, those of the thiazolineseries, those of the benzoxfazole series, those of the benzoselenazoleseries, those of the benzimidazole series, and those of the 2quinolineseries, and (b) at least one Watersoluble compound selected from theclass represented by the following general formula:

Ra R0 R1 Rin wherein R8 represents a member selected from the groupconsisting of -an acylarnido group and a sulfo group, R9 represents amember selected from the group consisting ofy an acylamido group yand asulfoaryl group and R111 represents a member selected from the groupconsisting of a hydrogen atom land a sulfo group, said compound (b)containing at least one sulfo group.

`6. `A photographic gelatine-silver-halide developingout emulsionsensitized with a supersensitizing combina tion of (a) a complex cyaninedye selected .fromthevclass represented Y byA the following generali.iorrrlilla;4

. X wherein R, R1 and Reachrepresents lanr allyl-fgroup containing .fromIto. 4 carbonfatomsl; Rg represents ra.' member selectedfrom the.groupconsisting .of.;a.hydrogen ato'm andtan'rylgroup, )Grepresents anacidradical, lZ

represents the non-metallicxatms .necessary to. completeY a heterocyclicnucleus selected'from thseof the .naphthothiazole. 'series' and Zlfrep'resents, the. non-metallic; atoms necessary to co'mp'lete alieterocyclicznucleus ezfmherb'en'zo,i

thiazole series, and (b) a water soluble compound se?A lected from theclass represented by the following geinlm eral formula:

SOaM wherein B1 represents anrember selected from the group consistingof a 2-beni6t'riaio1yl"groupand a 1,3,5-triazin- 6-ylamino group, B2represents anaroma-t-ic group, and M represents a cation. i

7g A: photographic` gelatinsilverfhalide.. developingf, outemulsonsensitized. withi arsupersensitizing combina- 8. A photographiegelatinofsilverfhalide,.v developingf, out emulsion sensitized with" asupersensitizing 4ornbina tion of (a) acomplex cyanine dye selectedfrom' the class represented by.. the following general formula:

wherein R,VR1, and R' each represents ann-alkyllgroup.,

containing from 1 to 4 carbon atoms, R2 represents a member selectedfrom thegroup consisting of a hydrogen tion of (a) avcomplexy cyaninedye selected from the classv represented bythe; following`gle'suileyrell formula:

w11ereincR,` R1. and .R. eachrepresentsrannalkyl-llgroupcontainingllfrom..11 to. 4,4carbon; atoms, R2 represents. a member.selected-.frommegroup consisting. ofga .hydrogen atom and an arylgroup, X represents...an acid..-radicahl Z.: represents` 'the`.nonemetallie atoms.. ,necessary5 to completeia. heterocyclcnuclensiselected:fromcthose ofethe benzothiazoler.. series.` andiZlLYrepresents the..nonmeta1lic atoms necessary to complete.alheterocyclicenucleus. of, the benzoselenazole series, and (b) awater-soluble compound selected from the' classwrepresentedhby thefollow;

wherein- R8 .represents a.member..selected Ifrom.thegrouptconsistinglof'ran.cylamidorgroup ,and a sulfo. group Rg. representscamember Aselected.:fromthe4 groupl consisting. of. an .i acylamido. group`and a sulfoaryl groupt. and R19 represets-a. member selected fremthe.grop consisting` of ar hydrogen .atoml ndfasulfmgi-oup, said compoundlbrcontaining at Aleast one .sulfd grloupr Q12".A` ,photographicA.gelatino-silYer-halide developing out` emulsin.- sensitiz'ed'..with aAsupersensitiz i11g combina-'f tiOnHo-(a) a complez-cyanine `dye selectedfrom-the class representedA byA thefollowing general-formular Y whereinR, R1 and R ca h represents an alkyl group containing from l to 4.carbon ,atoms, R2 represents a member selected fromx the Egroupconsisting of a hydrogen atom and an aryl group, i:TX representslan acidradical,

Z represents the non-metallic atoms'necessary to complete a heterocyclicnucleus selected from those of the benzothiazple series and Z1represents the norgmetallic ator'fs necessarytxfcomplet'"afhteroeyclic;nucleus ofv the -n'aphtho'thiazole'serie'sa'and (Ig) lawater-soluble come pound 'selected from the classrepresented thee-following generali.formula i wherein Rarepresents;fasnepljss-ssetegfirgmf thejgrcnf consisting of an acylamidogroup and a sulfo group, R9' represents a memberV Aselecta(lm rfraomthegroup consisting of an aylarnido Vgro an a Vsulfoaryl groupand R10represents a"m'ember"selected frorn"`the7grup"consistng of a hydrogenatom and= a sulfo group, said compound (b) containing at least one sulfogroup.

133A., photographigSgelatinoesilverhalide ndgtgelopigg@ d w i 21iz-phenylethylidenel -2- (Z-naphtho 1,2]thia'zo1y1eth0-ptoluenesulfonate)methylene]-4-thiazolidinone and 3,7- bis(2phenylbenzamido) 2,8 disulfodibenzothiophene- 5,5-dioxide sodium salt.

16'. A photographic silver bromiodide emulsion sensi tized with asupersensitizing combination of (a) at least one complex cyanine dyeselected from the class represented by the following general formula:

14. A photographic gelatine-silver-halide developingout emulsionsensitized with `a supersensitizing combination of (a) a complex cyaninedye selected from the class represented by the following generalformula:

Il Ra C -N--R wherein R8 represents a member selected from the groupconsisting of an acylamido group and a sulfo group, R9 represents amember selected from the group consiting of an acylamido group and asulfoaryl group and R10 represents a member selected from the groupconsisting of a hydrogen atom and a sulfo group, said compound (b)containing at least one sulfo group.

15. A photographic gelatino-silver-halide developingout emulsionsensitized with a supersensitizing combination of 5 1,3-diethyl-2(3H)benzimidazolylidene) ethylidene] -3ethyl-2[ 2-naphtho[ 1,2] thiazolyletho-p-toluenesulfonate)methylene]-4-thiazolidinone and 3,7-bis(2phenylbenzamido) 2,8 disulfodibenzothiophene 5,5- dioxide sodium salt.

`\ D, f' X wherein R and R1 each represents an `alkyl group, R2represents a member selected from the group consisting of a hydrogenatom, an alkyl group, and an aryl group, Q represents a member selectedfrom the group consisting of a methine group and a nitrogen atom, Xrepresents an acid radical, n, m and d each represents a positiveinteger of from 1 to 2, D and D1 together represent the non-metallicatoms necessary to complete a heterocyclic nucleus selected from thegroup consisting of those of the 4-thiazolidinone series, those of the5-thiazolidinone series, and those of the 4-imidazolidinone series, andZ and Z1 each represents the non-metallic atoms necessary to complete aheterocyclic nucleus containing from 5 to 6 atoms in the heterocyclicring, and (b) at least one watersoluble compound selected from the classrepresented by the following general formula:

o o R s Re wherein R8 represents a member selected from the groupconsisting of an acylamido group and a sulfo group, R9 represents amember selected from the group consisting of an acylamido group and asulfoaryl group and R10 represents a member selected from the groupconsisting of a hydrogen atom and a sulfo group, said compound (b)containing at least one sulfo group.

References Cited in the tile of this patent UNITED STATES PATENTS2,186,717 Eggert et al Jan. 9, 1940 2,304,962 Sheppard et al. Dec. l5,1942 2,420,631 Taylor May 13, 1947 3,440,119 Riester et al Apr. 20, 19482,694,636 Keller Nov. 16, 1954 2,718,466 Wolfson Sept. 20, 1955 UNTTTDsTATTs PATENT oTTToT CE'NHCATE @ll CUREUHON Patent No., 2,94763O August2 1960 Jean E Jones d that error appears in the printed specification ltis hereby certifie ring correction and that the said Letters of theabove numbered patent requi Patent should read as corrected below.

the right-hand portion voi" the Column lu lines 58 .to 62g as in thepatent:

formula should read as shown below instead o for "polyearbocyelie ColumnlI line Column 3 line 251,

for "an" read w can 2Aq for grop" read e group n Signed and sealed this18th day of April l9l Attest'ing @meer Commissioner of Patents

1. A HOTOGRAPHIC SILVER HALIDE EMULSION SENSITIZED WITH ASUPERSENSITIZING COMBINATON OF (A) AT LEAST ONE COMPLEX CYANINE DYESELECTED FROM THE CLASS REPRESENTED BY THE FOLLOWING GENERAL FORMULA: